Cluster currently uses Twitter, Facebook, Google, or Apple accounts for login, and login through mail addresses only exist for compatibility with accounts made at the early stage of service provision. As a result, most users will not be able to login with an email and a password. You will, however, be able to log in without a social media account if you have recently created a new account from the mobile app version.
You also cannot use your email address linked to your account as a login, unless it is through the Twitter/Facebook/Google/Apple account login.
(We ask users to register email addresses in the case that we need relay information about avatars, worlds, and events.)